1. Field of the Invention
The present invention relates to microwave antennas, and more particularly to a flush mounted dual frequency band antenna.
2. Description of the Prior Art
Prior design art for dual frequency-dual mode antennas has been defined by several authors in the IEEE Transactions on Antennas and Propagation: Wolfgang H. Krammer described the properties of half wave slots in a two mode rectangular waveguide in the March 1973 issue; and Maurice L. Fee reported the design of a dual frequency trough waveguide in the November 1972 issue. Other design methods for antennas that radiate frequency bands separated by greater than an octave include log periodic antennas and cavity backed spiral antennas.